### Upcoming Talks

#### Zahlentheoretisches Kolloquium

Title: Average bounds for l-torsion in class groups
Speaker: Dr. Christopher Frei (University of Manchester)
Date: Freitag, 13. 7. 2018, 14:15 Uhr
Room: Seminarraum Analysis-Zahlentheorie (NT02008), Kopernikusgasse 24/II
Abstract:

Abstract: Let l be a positive integer. We discuss improved average
bounds for the l-torsion of the class groups for some families of number
fields, including degree-d-fields for d between 2 and 5. The
improvements are based on refinements of a technique due to Ellenberg
and Venkatesh. This is joint work with Martin Widmer.

#### Vortrag im Seminar für Kombinatorik und Optimierung

Title: Graph limits of random unlabelled k-trees
Speaker: Yu Jin (Technische Universität Wien)
Date: Dienstag 3.7.2018, 14:15
Room: Seminarraum AE06, Steyrergasse 30, Erdgeschoss
Abstract:

We study random unlabelled $k$-trees by combining the colouring approach by Gainer-Dewar and Gessel (2014) with the cycle pointing method by Bodirsky, Fusy, Kang and Vigerske (2011). Our main applications are Gromov--Hausdorff--Prokhorov and Benjamini--Schramm limits that describe their asymptotic geometric shape on a global and local scale as the number of hedra tends to infinity.

This is the joint work with Benedikt Stufler.